Description of problem:
spacewalk-hostname-rename script do not support IPv6 address.


Version-Release number of selected component (if applicable):
spacewalk-utils-1.6.6-1.el5


How reproducible:
always


Steps to Reproduce:
1. Install SW1.6 on system with IPv4 network
2. Configure IPv6 address and hostname for that system (DNS have forward
   and reverse entries for that hostname only as IPv6)
3. Try to "rename" the SW server


Actual results:
# spacewalk-hostname-rename 1234:56:0:789b:223:7dff:fe4c:1234
Error: Invalid option 1234:56:0:789b:223:7dff:fe4c:1234
Usage:
   spacewalk-hostname-rename <IP_ADDRESS> [ --ssl-country=<SSL_COUNTRY> --ssl-state=<SSL_STATE> --ssl-org=<SSL_ORG> --ssl-orgunit=<SSL_ORGUNIT> --ssl-email=<SSL_EMAIL> --ssl-ca-password=<SSL_CA_PASSWORD>]
   spacewalk-hostname-rename { -h | --help }


Expected results:
Should work


Additional info:
This is caused by this option check:

            [[:digit:]]*.[[:digit:]]*.[[:digit:]]*.[[:digit:]]*) IP=$1;;

Going further you will run into issue with function check_input_ip.